git graph has branch with no branch-off point? -

i can't explain other screenshot:

what in world mean? feat-zoo branch seems stem nowhere.

edit:

per requested, script used generate this. run script, @ graph, start over, remove sleep 2 calls , you'll different result matches screenshot above.

#!/bin/sh  [ -d .git ] || git init  act="rebase"  echo "blah blah" > file1.txt echo "another file" > file2.txt git add file1.txt file2.txt git commit -m "master c1" sleep 2  echo "new line here" >> file1.txt echo "new file" > file3.txt git add file3.txt git commit -a -m "master c2" sleep 2  echo "bug fixes" >> file1.txt echo "bug fixes" >> file3.txt git commit -a -m "master c3" sleep 2  git branch feat-zoo  echo "magical" >> file2.txt git commit -am "master c4" sleep 2  git checkout feat-zoo git $act master echo "new end" >> file3.txt git commit -am "br c1" sleep 2 echo "**end" >> file2.txt git commit -am "br c2" sleep 2  git checkout master sed -i 's/blah blah/wheee/' file1.txt git commit -am "master c5" sleep 2  git checkout feat-zoo git $act master  echo "final" >> file1.txt git commit -am "br c3" sleep 2  git checkout master echo "done" > signoff git add signoff git commit -m "master c6" sleep 2  git merge feat-zoo 

when run script (with 1 change sed command, adding -e, right thing on box, , adding -m "merge branch 'feat-zoo'" merge, don't have manually finish edit session), works fine or without "sleep 2"s.

$ git log --graph --decorate --oneline --all *   5847d16 (head, master) merge branch 'feat-zoo' |\   | * 42eb472 (feat-zoo) br c3 | * 28f0d24 br c2 | * 967e122 br c1 * | 136b44a master c6 |/   * 437cf27 master c5 * 4c0edac master c4 * 6dbf80e master c3 * 95c61ec master c2 * 597d9ba master c1 

if create orphan branch , merge in, works fine too.

what viewer using view these? suspect it's attempting draw graph, , place commits, using commit time-stamps, , getting confused because br c1's parent master c5 it's drawn master c5 above, has no place "below" br c1 connect next line. when runs out of commits draw stops drawing, giving output see. try git log command above; think show same thing get.

(in other words, looks bug in viewer, not in git.)